1. Field of the Invention
This invention relates to an improvement of the blowing-out characteristics of an air brush, and more particularly, relates to an air brush able to blow-out paint ejected from a nozzle from a starting point to the line of a predetermined width at the beginning of writing of the line so as to be naturally transferred, and able to easily perform a basic operation of the air brush for completely writing the line even by a beginner while the line is naturally tapered from the line of a predetermined width.
2. Description of the Related Art
FIGS. 11 and 12 show a conventional air brush 100. This air brush 100 has an air brush main body 101 having a nozzle 102 at its tip and approximately formed in a long sleeve shape.
A needle 103 is inserted along a shaft core portion within the air brush main body 101 so as to be freely advanced and retreated. The air brush 100 is constructed such that a compressed air is supplied to an air supply port 104 connected to an intermediate portion of the air brush main body 101, and is introduced to an air passage path 112 within the air brush main body 101 through an air valve 105, and is blow out of the above nozzle 102. The above air valve 105 has a structure in which the air valve 105 is opened by pushing a valve rod 105a. 
In the air brush 100, an operating rod 106 is fitted and mounted to a notch port 121 notched and formed in the intermediate portion on the upper face of the air brush main body 101. A pushing rod 108 is connected to a lower end portion of this operating rod 106 through a pivotal shaft 107 so as to be freely bent. The pushing rod 108 is supported such that the pushing rod 108 is inserted and fitted into an insertion hole 109 bored within the air brush main body 101 so that the pushing rod 108 is slid in the axial direction together with the operating rod 106. A tip portion of the above pushing rod 108 abuts on the tip of the valve rod 105a of the air valve 105. An operating button 106a for placing a finger is arranged at the upper end of the above operating rod 106.
On the other hand, the valve rod 105a is mounted into a connecting sleeve 110 as an air supply port, and is upward biased at any time by the biasing force of a coil spring 111, thereby maintaining a state (valve closing state) in which an upper end portion of the above valve rod 105a abuts on the tip of the pushing rod 108 (FIGS. 11 and 12).
When a user pushes down the operating rod 106 of the above air brush 100, the valve rod 105a is pushed down through the pushing rod 108 so that the air valve 105 is opened. Thus, the compressed air is supplied into the air brush main body 101 from a supply source of the compressed air connected to the above connecting sleeve 110, and is ejected from the nozzle 102 through the air passage path 112.
When the user pulls the operating rod 106 pushed down as mentioned above backward as it is and is tilted with the pivotal shaft 107 as a fulcrum, the needle 103 gripped and supported by a needle chuck 113 is retreated, and the paint supplied from a container 112 for paint is sprayed and ejected by the ejection of the compressed air. The operation for pushing and then pulling the operating rod 106 as mentioned above is called a double action, and this double action is a basic operation in the use of the air brush.
When a thin line is drawn by using the above conventional airbrush 100, the air is blown out of the nozzle 102 by slightly pushing-down the operating rod 106. Next, a small amount of paint is supplied to the nozzle 102 by slightly pulling the operating rod 106 while this operating rod 106 is pushed. Thus, a line gradually widened in width from a starting point is written. Namely, as mentioned above, the double action as the basic operation of the air brush is taken. The blowing-out of the paint is increased by further pulling the operating rod from the above state so that a thick line can be drawn.
Thus, when the line is drawn by using the air brush 100, a write-beginning portion of the line is gradually thickened from the starting point and a constant thick line is formed by slightly pulling the operating rod 106 while the operating rod 106 is very slightly pushed. However, the operation of pulling the operating rod 106 little by little while the operating rod 106 is pushed little by little, is an operation requiring concentration force even in a veteran.
Accordingly, it is difficult for a person never using the air brush or a beginner to smoothly perform the above operation of the operating rod. Since no adjustment of pushing and pulling degrees of the operating rod is first known, the paint is brown out at once at the write-beginning inmost cases, thereby resulting in a failure.
The operation of the operating rod of the air brush is gradually progressed by repeating practice. However, when the beginner first fails in this operation, it seems very difficult to use the air brush. As a result, there is also a case in which weak consciousness is caused in the use of the air brush, and the use (the drawing of a work by using the air brush) of the air brush itself is abandoned.
On the other hand, when the operating rod is operated as mentioned above, the paint begins to be ejected after the air is first blown out. When this operation is reversely performed, the paint is blown off by the air after the paint is collected in the nozzle. Therefore, the paint is ejected at a stroke at the starting point of the line, thereby resulting in a failure.
After the line is written, the blowing-out of the air is stopped after the ejection of the paint is stopped. When this operation is reversely performed, the paint is left in the nozzle after the blowing-out of the air is stopped. Therefore, in the next blowing-out, the paint left in the nozzle is brown out at a stroke.
In contrast to the above conventional airbrush, an object of the present invention is to provide an air brush having a function in which even a beginner can easily perform an operation for pulling the operating rod (ejecting the paint) little by little while the operating rod is slightly pulled (the air is ejected) at an initial stage of the drawing of a line requiring a technique and an experience.
To solve the above problems, in the air brush of the present invention, a needle is inserted in the axial direction along a shaft core portion of an air brush main body having a nozzle at its tip so as to be advanced and retreated. The amount of paint ejected from the nozzle is adjusted by advancing and retreating this needle.
An air valve is arranged within the air brush main body, and a compressed air supplied through this valve is blown out of the above nozzle. An operating rod is fitted into a notch port formed in the air brush main body, and a pushing rod is connected through a pivotal portion arranged at the lower end of this operating rod so as to be freely bent. This pushing rod is fitted into the air brush main body, and is supported together with the above operating rod so as to be freely vertically pushed and moved.
Since the lower end of the above pushing rod and the upper end of a valve rod for opening and closing the air valve are opposed to each other, the air valve is opened by pushing and moving the valve rod by pushing the operating rod so that the compressed air is supplied to the nozzle. The amount of the air supplied to the nozzle, i.e., the blowing-out amount is approximately proportional to the pushing amount of the above operating rod.
On the other hand, when the above operating rod is tilted backward, the needle is retreated in cooperation with an engaging body mounted within the notch port of the air brush main body. The nozzle is opened by retreating the needle, and the paint supplied by blowing-out the air is sprayed.
A slanting face projected while the slanting face is inclined from below to above, is formed on the front face side of the above operating rod. This slanting face abuts on an abutting portion of a front side edge of the notch port of the air brush main body.
The air valve is pushed and opened little by little and the needle is simultaneously retreated little by little in a range in which the slanting face of the operating rod and a contact portion arranged at a front side edge of the notch port come in contact with each other and are slid at the initial stage of an operation for pushing and moving the operating rod.
Namely, at the initial stage of the operation of the operating rod, a user can increase the amount of the air ejected from the nozzle and the amount of the paint supplied to the nozzle little by little from zero by only slightly pushing the operating rod. Thus, even a beginner can simply express the beautifulness of a line naturally enlarged from a starting point and conventionally considered as the technique of a veteran by a little exercise.
In the gist of the air brush according to claim 2, a slanting face projected while the slanting face is inclined from below to above, is formed on the rear face of the operating rod fitted into the notch port of the air brush main body. This slanting face abuts on the engaging body mounted within the notch port of the air brush main body.
The air valve is pushed and opened little by little and the needle is simultaneously retreated little by little in a range in which the slanting face on the operating rod rear side and the engaging body mounted within the notch port come in contact with each other and are slid at the initial stage of the operation for pushing and moving the above operating rod.
Thus, at the initial stage of the operation of the operating rod, the user can increase the amount of the air ejected from the nozzle and the amount of the paint supplied to this nozzle little by little from zero by only slightly pushing the operating rod. Thus, even a beginner can express the beautifulness of a line naturally enlarged from a starting point and considered so far as the technique of a veteran.
In the gist of the air brush according to claim 3, slanting faces projected while the slanting faces are inclined from below to above, are respectively formed on the front and rear faces of the operating rod fitted into the notch port of the air brush main body. A front side edge contact portion of the slanting face on this operating rod front side and the notch port, and the engaging body fitted and mounted into the notch port abut on each other.
The user pushes and opens the air valve every small amount and simultaneously retreats the needle every small amount in a range in which a front side edge contact portion of the slanting face on the operating rod front side and the notch port, and the engaging body fitted and mounted to the notch port come in contact with each other and are slid at the initial stage of the operation for pushing and moving the operating rod.
Thus, at the initial stage of the operation of the operating rod, the user can increase the amount of the air ejected from the nozzle and the amount of the paint supplied to this nozzle little by little from zero by only slightly pushing the operating rod. Thus, the beautifulness of a line naturally enlarged from a starting point can be expressed.
In the air brush according to claims 4-6, a timing stroke for making the ejection of the air precede the supply of the paint in the pushing of the operating rod, and delaying the ejection of the air with respect to the supply stoppage of the paint in release of the pushed operating rod is arranged below the slanting face in the above operating rod. Accordingly, when the operating rod is pushed, the blowing-out of the air is precedently performed in the range of the above timing stroke at the initial stage of this operation of the operating rod, and the paint is then ejected. Thus, the phenomenon that the paint collected in the nozzle is blown off at a stroke by the air, can be prevented by delaying the supply of the paint in comparison with the ejection of the air.
Further, the supply of the paint is stopped in the stoppage of the blowing-out of the paint. After the supply of the paint to the nozzle is stopped by the delay using the timing stroke, the blowing-out of the air is stopped with an instant delay. Thus, no paint is left in the nozzle, and no paint left in the nozzle is blown out at a stroke in the next use.